Clinical observations have suggested that the neuropsychological profile of early and late onset forms of Alzheimer's disease (EOAD and LOAD) differ in that neocortical functions are more affected in the former and learning in the latter, suggesting that they might be different diseases. The aim of this study is to assess the brain structural basis of these observations, and test whether neocortical areas are more heavily affected in EOAD and medial temporal areas in LOAD. Fifteen patients with EOAD and 15 with LOAD (onset before and after age 65; Mini Mental State Examination 19.8, SD 4.0 and 20.7, SD 4.2) were assessed with a neuropsychological battery and high-resolution MRI together with 1:1 age- and sex-matched controls. Cortical atrophy was assessed with cortical pattern matching, and hippocampal atrophy with region-of-interest-based analysis. EOAD patients performed more poorly than LOAD on visuospatial, frontal-executive and learning tests. EOAD patients had the largest atrophy in the occipital [25% grey matter (GM) loss in the left and 24% in the right hemisphere] and parietal lobes (23% loss on both sides), while LOAD patients were remarkably atrophic in the hippocampus (21 and 22% loss). Hippocampal GM loss of EOAD (9 and 16% to the left and right) and occipital (12 and 14%) and parietal (13 and 12%) loss of LOAD patients were less marked. In EOAD, GM loss of 25% or more was mapped to large neocortical areas and affected all lobes, with relative sparing of primary sensory, motor, and visual cortex, and anterior cingulate and orbital cortex. In LOAD, GM loss was diffusely milder (below 15%); losses of 15-20% were confined to temporoparietal and retrosplenial cortex, and reached 25% in restricted areas of the medial temporal lobe and right superior temporal gyrus. These findings indicate that EOAD and LOAD differ in their typical topographic patterns of brain atrophy, suggesting different predisposing or aetiological factors.
Patients with MCI-V have a distinctive clinical picture and can be identified in a clinical setting. Because of the high frequency of adverse outcomes, very early preventive measures need to be devised.
Background: The diagnosis of mild cognitive impairment (MCI) is clinically unhelpful, as many patients with MCI develop dementia but many do not. Objective: To identify clinical instruments easily applicable in the clinical routine that might be useful to predict progression to dementia in patients with MCI assessed in the outpatient facility of a memory clinic. Participants and methods: 52 dementia-free patients (mean (standard deviation) age 70 (6) years; 56% women) with MCI, and 65 healthy controls (age 69 (6) years; 54% women) underwent brain magnetic resonance scan with standardised visual assessment of medial temporal atrophy (MTA) and subcortical cerebrovascular lesions (SVLs). Follow-up assessment occurred 15.4 (SD 3.4) months after baseline to detect incident dementia and improvement, defined as normal neuropsychological performance on followup. Results: Patients were classified into three groups according to the presence of memory disturbance only (MCI Mem), other neuropsychological deficits (MCI Oth) or both (MCI Mem+). MCI Mem and Mem+ showed MTA more frequently (31% and 47% v 5% and 14% of controls and MCI Oth, p,0.001). 11 patients developed dementia (annual rate 16.5%) and 7 improved on follow-up. The only independent predictor of progression was MTA (odds ratio (OR) 7.1, 95% confidence interval (CI) 1.4 to 35.0), whereas predictors of improvement were the absence of memory impairment (OR 18.5, 95% CI 2.0 to 171.3) and normal MRI scan (OR 10.0, 95% CI 1.7 to 60.2). Conclusion: Neuropsychological patterns identify groups of patients with MCI showing specific clinical features and risk of progression to dementia. MTA clinically rated with a visual scale is the most relevant predictor of progression and improvement.
The visual rating scale of MTA, easily applicable in clinical practice, shows good agreement with more demanding quantitative methods, and can discriminate AD patients from controls with good accuracy.
Background
The optimal surgical margins assessment is capital in oral squamous cell carcinoma (OSCC) management. We evaluated the clinical benefits of integrating intraoperative macroscopic margin (MM) assessment and narrow band imaging (NBI).
Methods
Sixteen OSCC patients eligible for surgery were prospectively enrolled. For each patient, 2 to 6 bioptic samples of MM and NBI margins were obtained and histologically analyzed for the presence of dysplasia and lymphocytes. Microvessel density was investigated by CD34 immunohistochemistry.
Results
Taken together, 104 specimens were analyzed, including 15% tumors, 33% MM, 33% NBI margins, and 19% MM-NBI overlapping margins. The NBI margins were closer to the lesion in 50% cases, while the same number of MM were more conservative than NBI, irrespective of the tumor site. The rate of histologically positive margins was similar among the two methods, akin to the microvessel density.
Conclusions
MM assessment should be integrated but not replaced with the NBI technology to allow for more conservative surgery.
Persons in the IBNA study had clinical and neuropsychological features consistent with that of the general population. Their brain morphometric features may be used as normative references for patients with suspected neurodegenerative disorders.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.